In retail outlets it is difficult to display many families of products together and allow easy selection of a particular product by a customer: This can lead to a customer-becoming frustrated by the selection process and either rot purchasing a product or else making the wrong selection. Furthermore, display units which can display many families of products together are expensive and difficult to install. They also provide low product density, that is to say, they do not allow many products to be displayed in a given area. This increases the cost of displaying a number of families of products. Also, in known prior art devices, if a particular family of products is discontinued or if a new family of products is introduced, it can be time consuming and expensive to change the display of products to accommodate such changes. In known devices, information relating to a family of products and to each product within that family cannot be clearly presented. Also, known display units have to be transported to a retail outlet without the products to be displayed installed. Installing the display products in the retail outlet in a display area can be time consuming and expensive. It can also lead to a loss of sales whilst the display area is disrupted.